The Japan Radiation Scare

As fires and explosions continue at Japan’s Fukushima Daiichi nuclear complex, anxiety about radiation sickness mounts, including whether the disaster will ultimately affect the United States. A new explosion Tuesday morning was the third in four days at the plant — prompting Prime Minister Naoto Kan to encourage citizens within about 20 miles of the Fukushima complex to stay indoors to avoid exposure to radiation.

Not surprisingly, Japan’s tragedy has revived frightening memories of nuclear meltdowns at Chernobyl in 1986 and Three Mile Island in 1979, but the truth is all three were very different events. And as a result of Three Mile Island and Chernobyl, nuclear power plants today have adopted more stringent safety measures and backup containment programs.

“It’s important to remember that when Three Mile Island melted down, there was no unplanned release of radiation, and there were no deaths from radiation,” says Jeff Geuther, nuclear reactor facility manager at Kansas State University. People tend to get frightened by threats of radiation, but so far the levels detected outside of the immediate vicinity of the Fukushima power plant are not considered dangerous.

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According to news reports, officials in Tokyo (about 150 miles south of the Fukushima Daiichi nuclear reactors) said radiation there was 10 times the usual level but still posed no threat to human health.

So just how concerned about radiation poisoning should you be? Everyday Health took your top questions to experts for answers.

1. Should West Coasters worry about radiation sickness?

Residents of Hawaii, the U.S. Territories, Alaska, and Washington, Oregon, and California should stay calm, experts say. Those contacted by Medpage Today (a sister company of Everyday Health) for the most part agreed that while radioactive particles will eventually reach the United States, the levels will be too low to impact people’s health.

“You have to consider a number of factors,” according to Tom Hei, PhD, Associate Director of the Center for Radiological Research at Columbia University Medical Center in New York, in an interview with Everyday Health. “How much radiation is being released into the atmosphere, the direction of the wind current, which compounds are being released, and their half-life — the amount of time it takes them to decay. From what we’ve heard so far, the radioactivity detected [in Japan] has been minimal.”

That’s because, thankfully, the release of radioactive particles seems to be confined to containment structures within the Japanese plant.

To further put things in perspective, keep in mind that when the United States tested nuclear and hydrogen bombs in the Pacific Ocean and dropped atomic bombs in Japan during World War II, they released “far more radiation than these [Japanese] power plants would ever come close to releasing, and it all dissipated in the atmosphere, at least from the standpoint of any health implications in the U.S,” said James Thrall, MD, radiologist-in-chief at Massachusetts General Hospital in Boston and president of the American College of Radiology, in an interview with MedPage Today.

2. Are there any long-term risks from the radiation leakage?

While acute radiation sickness is currently not a threat to people other than Fukushima workers or those who live in close proximity to the plant, the radiation leakage may have long-term health implications. After a large leak, about 75 percent of the radiation eventually winds up in the ground and water supply nearby, which means it can contaminate vegetation, livestock, and cow’s milk, says Leslie M. Beitsch, MD, director of the Center for Medicine and Public Health at Florida State University College of Medicine in Tallahassee. As people ingest contaminated food and water, their long-term risk for thyroid and other cancers, such as leukemia, increases. Thyroid cancercan take 8 to 12 years to develop after radiation exposure, according to the American Thyroid Association; leukemia can strike within a few years, according to the American Cancer Society.

The remaining 25 percent of the leaked radiation can stay in the atmosphere for extended periods of time, depending on particle size. “If that happens, it does become a global concern, because once these particles reach the upper atmosphere, they can disseminate everywhere,” says Dr. Beitsch. “It’s a potential risk, but a small one at this point.”

However, the radioactive particles would be so widely dispersed that the risk of exposure to any one person is extremely minor, Beitsch adds.

3. Who’s most at risk from radiation exposure?

Fetuses, infants, and small children face the greatest potential harm from radiation. That’s because radiation causes damage by mutating DNA in cells, which can lead to cancer. Because young children’s cells divide at a much faster rate than those of adults, they face potentially more serious long-term health issues, including neurological problems as well as cancer.